PURPOSE: To prevent the contamination with heavy metal and to carry out superior film formation by forming a refractory metal film by removing a naturally occurring oxide film from the surface of a substrate in a first treatment chamber and then conveying the above substrate into a second treatment chamber in vacuum.

CONSTITUTION: A silicon wafer 5 is taken out from a wafer carrier 28 in a storage section 4 by means of a hand arm 26 in a conveyance chamber 3 maintained at a reduced pressure. A gate valve 25a is opened and the wafer 5 is conveyed into a first chamber 1 by means of the hand arm 26 to undergo cleaning treatment consisting of the removal of the naturally occurring oxide film formed on the surface, to be treated, of the wafer 5 by means of dry etching. The treated wafer 5 is transferred to the conveyance chamber 3 by means of the hand arm 26 and conveyed into a second chamber 2, where a refractory metal layer is formed on the surface, to be treated, of the wafer 5 by means of CVD. Since the above treatments can be performed in the treatment chambers for their exclusive uses, respectively, a countermeasure can be made against contamination with heavy metal and precise film forming treatment can be carried out.